The Experiment
by novadiablo
Summary: Prompts, one-shots and whatever else Sherlock-related I feel like putting in here. Will always be NC-17, and if it's not, berate me for that fact, and then send me some crazy pills because I will have surely gone insane. Usually PWP
1. The Experiment

**A/N – Something I found with the skeletons in my closet that I've decided to make a three-parter (I know, I never finish them *slaps hand*). I should be doing my 'How John and Sherlock went from flatmates to consummating their marriage in eleven days', but I liked this one, because it's just such PWP. :D**

**ND**

"I need to run my tongue over your neck."

John flinches but doesn't look up from the filing cabinet.

"That's nice."

Sherlock's not sure how to take that answer.

"It's for an experiment," he states dumbly.

"Oh really? I though you just woke up with a craving."

Wh-wha? Oh. Sarcasm. What an annoying part of the English language. One should just say what they want to say.

"However for the experiment to be valid it must have an element of surprise."

John turns around holding a manila file.

"Sherlock, if you _ever_ licked my neck, whether or not you told me of your intentions, I would be surprised."

John tasted of soap and salt and his hair was wiry and smelt like strawberries. Sherlock would know. He'd just licked him.

Other observations:

John either did not enjoy or was completely surprised by this action.

When one is licked by their male flatmate, they jump of the couch, let out a string of swear words, lecture you on personal space and stalk off.

Sherlock did indeed have a libido.

Unfortunately for the experiment, the last point interested Sherlock the most.

He followed John back to his room, his head swimming, and his usually tiny amount of common sense drowned.

"You taste good." Sherlock said, his voice sugary and his head tipped forward.

John's Observations:

When having your shirt rucked up by your flatmate – who has just licked you – there is little more that you can do than stand their speechless.

John also had a libido (although this information was nothing new it was worth noting for referencing future events)

Sherlock was a slut.

This last point interested John minorly, however nothing more than Sherlock's tongue interested him much really after that.

Because Sherlock really was a slut (or a cat) - he was attempting to rub as much of himself against as much of John as possible while also trying to consume him. John pushed him back on the bed - Sherlock spread his legs as far apart as they could go (the guy was flexible even in suit pants) and began rutting up against John's hips, head pushed back and mouth open.

Sure, Sherlock hadn't had sex in a long time (ever, if we were being honest) and John was more than happy to oblige him, but first he dragged off those expensive pants (already saturated) and was pleasantly surprised at the lack of underwear he found there. A shiver ran down his spine as his mind ran through all of the times he'd touched…

He stood back for a moment to take in the picture, despite whimpered protests. Sherlock Holmes was lying pantless on his bed, arching upwards, and eyes rolling into the back of head, mouth open and gathering spit at the edges. His breathing was harsh, his arm and legs were spread wide, and that ridiculous purple silk shirt was stained with pre-come leaking from his throbbing member that was thrusting into nothingness.

_Sherlock Holmes_ was lying on his bed and the only thing he wanted in the world was John H. Watson, apparently, by the way he was moaning John's name. Which is probably what prompted John to do what he did next (and something he'd never done, so kudos to him for bravery), an act that involved taking as much of Sherlock's penis into his mouth as possible. Of course, John did choke (something he was prepared for, he _is_ a doctor), however the absolutely guttural groan Sherlock as he scrabbled at the sheets and spread his legs impossibly far apart was definitely worth it. John pulled his mouth off after a few seconds of Sherlock whimpering and stood up. He inspected Sherlock while he was undoing his belt (at lightning speed) – the way Sherlock too-thin chest rose and fell quickly, the way his eyes were hooded and his red mouth lay open, emitting a light 'hnnnnng' every now and then. John saw the whiteness of Sherlock's knuckles that gripped the sheets like vices and the way the pre-come matted Sherlock's pubic hair.

And John jumped back on top of Sherlock. The first proper foreskin on foreskin contact sent an electric shock through John and he moaned into Sherlock's hair. Sherlock rutted against John, clawing at his back now and writhing in fiery ecstasy. This wasn't going to last long, John realised as he squeezed his fingers into Sherlock's thighs, moving them upwards, his breath becoming harsher. He reached underneath his body and pressed his thumb and against Sherlock's perineum and that was all, folks. John locked his eyes onto that beautiful, sharp face as he felt warmth splash his chest and ended just moments afterwards.

John lay with his face in Sherlock's neck for a little longer before standing up and shuffling (he still had jeans on) into the bathroom to clean himself up. He looked into the mirror and saw a mess, and dread spread through his heart – not because his favourite shirt might not ever be rid of these stains, but because Sherlock would be stupid to want him. His hair was completely ruffled and he generally looked horrible.

He stood there looking at himself, lost in thought, for about three minutes before he realised he hadn't moved. He buttoned and belted himself up and stood in Sherlock's gaze, awaiting the verdict.


	2. The Dark

Prompt: Sherlock's brain never stops but in the dark he can only think about sex. PWP.

John felt his heart beating in his ears as he ran down the hallway behind Sherlock, through an open door. After that the ground disappeared from under his feet and Sherlock caught him around the waist, stopping him from falling but unfortunately unable to prevent him from rolling his ankle. They hobbled down the stairs, their harsh breathing the only thing breaking the silence. It was so dark John couldn't see his own hand, could only feel Sherlock's around him. They slumped against something that was probably a wall and John gingerly felt his ankle for swelling.

"Is he going to come after us?" he panted to Sherlock, who was beside him and recovering quickly.

"No, I threw my shoe through the window so he'll think we went through there."

John ignored the fact that the shoe had probably cost more than he made in a month and focussed on Sherlock massive error.

"Sherlock, it was the second floor that we were on!"

"Yes," Sherlock said in his voice that indicated John was very stupid, "and I'm Sherlock Holmes, and you got a sprained ankle for your troubles anyway."

John shrugged, because Sherlock was right, he probably would jump out a second story window.

"So how are we going to get out?" He asked, because Sherlock generally thought about one hundred and two steps ahead, so he'd know.

"I don't know."

John froze. Shit. Why not?

"How the hell can you not know!"

"I can't think in the dark," Sherlock said very quickly, but his voice broke on the 'k'.

John frowned at this but was more surprised by the admission.

"You can't think in the dark?" John stated, deadpan.

"No, yes, no – I can, just not about cases or survival or stuff." Sherlock uttered awkwardly.

"So… why not?"

Sherlock shrugged.

"Why can't you think in the dark, Sherlock?" John began, teasingly.

Sherlock turned away and shrugged again.

"Why not Sherlock?" he mocked, poking him.

"Shut up John your voice is making it worse."

"Making what worse?"

They sat in silence for a moment and Sherlock's breathing became ragged.

"Are you okay, Sherlock?"

A clipped "Fine."

"Why can't you think in the dark, Sherlock?" John asked, seriously this time.

"My brain associates dark with sex. When Mycroft and I were younger we had a very strict nanny who tucked us in tightly with our arms above the sheets and left one light on all the time and I eventually figured out why and now when it's dark I can only think about sex."

John couldn't help it. He tried, he really truly did, kept his mouth closed until his ribs ached but when he burst out laughing he didn't feel any guilt.

"And so that's why you never sleep!" he eventually panted out between giggles.

"Shut up!" Sherlock yelled and punched him in the arm, but he was laughing too.

"And why you always have the lights on?" John was doubled over by now, but a sharp pain from his ankle brought him back to reality.

"It's pretty stupid, I know."

John realised that Sherlock was talking as close to a human being as he had since they'd met. The whole thinking about sex thing must have him pretty distracted… but if he's thinking about sex then did he have a…

"_Shut up John your voice is making it worse."_

John scrambled backwards and hit his head on a shelf. "Sherlock, how can you have an erection when it's only me and you in the room?"

Sherlock was silent and John felt a wave of lust run through him, which wasn't right at all. What the hell was his body thinking? Sherlock had an erection over John and he should find it disgusting? Right? RIGHT?

John crawled a little closer and then hiss as Sherlock unlocked his phone. "Ah, bright lights!" John almost screeched as Sherlock sighed and said, "I can think again."

"What are you doing?" John asked, crawling closer. Adjusting his eyes he saw an address and _the basement_ in a text sent to Lestrade. The message was sent when John had a good idea.

He pressed the lock button the top of the phone and swung his legs over Sherlock before he could react, effectively straddling him. Then John crushed their mouths together and it was around then that Sherlock brain short circuited. He grabbed onto John's hair and pulled him closer while John – always to the point – undid Sherlock's pants and dug his hands in, but was interrupted by Sherlock pulling him up and pushing him against the wall.

Finding the leverage better this way anyway, John concentrated hard on giving Sherlock at least a mediocre hand job, which is a difficult feat when a man you have suddenly become insanely attracted to is pulling on your lip with his _teeth_ and moaning like a sexy injured rhinoceros.

He gripped the warmth and experimentally pulled, and an almost painful bolt of pleasure ripped through him at the noise Sherlock made. This wouldn't last, John knew, by Sherlock's harsh breath and the impending entry of Lestrade and Co. However, as wet kisses were smushed into his neck, John heard the words 'Fuck me,' very clear in his ear.

"Not now, Sherlock."

"Please John," Sherlock moaned as John circled his fingers around the tip. He could feel Sherlock's body against him and it took all of his will power to not just drop his pants and take the man against the wall.

"Later, I promise."

Sherlock looked up at him, his hunched body barely able to hold its own, with hooded eyes and red lips and nodded. Well, there was no backing out now, John thought, as he whispered 'Come now', into Sherlock's ear and was rewarded with warmth spilling over his hands and the softest moan he'd ever heard. John buttoned Sherlock back up as best he could with the consulting detective a dead weight, but of course that was the point when Scotland Yard's finest burst through the door and switched on the light.

It was like Sherlock's 'ON' switch had been flicked as well. He stood straight up, but there was no denying what had just gone down. He had sweat dripping down his face, his eyes were drooping and his lips were red, and his hair… oh god his hair. John felt an odd straining against his jeans.

John walked out awkwardly, but Sherlock was already back on task as though nothing had happened. He was discussing the man with Lestrade loudly and flailing in all different directions, giving very direct instructions, after which Lestrade sent five of his men to the closest Primark.

They sat in the cab on the way home, Sherlock texting madly and John watching the orangey sky with a small amount of dismay. John ran up the stairs and flicked the light on, but as he was taking off his coat, darkness fell over him and a body was pressed up against his.

"You promised."


	3. Awkward

**A/N: This is set right after the invigorating chase after the taxi, when John forgets his cane and all of that jazz. Of course, Mrs Hudson doesn't interrupt them to tell them of Scotland Yard above their heads and awkward times ensue. Sherlock is very OOC and romanticised in this, I recently watched Small Island in which Benny is ridiculously sweet (in the beginning, anyway) and it sort of took hold.  
>Also, I don't like the fact that Lestrade needs a first name at all, however Gregory seems most likely (and is House's first name BUT WHATEVER), and stories that call him Gerald or Gresham or Grosvenor or whatever put me off. Gene is alright, now that I think about it, but I'll shut up now.<strong>

**A/N: I'm using Gene now. It's sexy. I considered Giles but this isn't Buffy.**

John's excuse would have been adrenaline.

Of course, he didn't get to use it because before he'd had the chance to even slightly regret his decision Sherlock Holmes' hands were on his waist and his quiet giggles were being consumed by a clumsy tongue. The cane that John had just received of Angelo fell to the ground as he hooked both hands around were on bony shoulders pushing them against the wall while one tongue slid against another and there was a groan.

"I thought you were married to your work," John, who may or may not have been responsible for the groan, whispered in Sherlock's ear.

"I need a blogger," Sherlock said, and he was joking and John found that quite wonderful, so he kissed the smile that had formed on those glorious lips.

It may have been a minute or twenty that they stood there, Sherlock with his back against the wall and John with a crick in his neck and a tongue in his mouth, but eventually chemicals that had not been very busy lately (John) or ever (Sherlock) began to kick and, truly, an erection tented in fitted pants was a lovely sight. This of course was the reason John decided to grind his very own against it, which was rather overwhelming for Sherlock, who not only let out a deliciously guttural moan but also decided that it was time to get naked and that perhaps their front hall wasn't the best place for that.

Detective Inspector Gene Lestrade had seen some pretty weird, horrific and awkward things in his life. However, the reactions of a makeshift drug squad at the sight of an assumed psychopath trying to remove the clothing of a man he'd met the day before while also possibly disembowelling the man with his tongue would have to top it.

In fact, it was made all the more awkward when the two buds noticed the volunteers (after a few extra seconds of not being sure one ended and the other began) there was complete and utter silence until Anderson had the good sense to almost yell "what the hell" and eyes were everywhere except the pair, who were now attempting to stuff themselves back into their respective trousers.

"What are you doing in my flat, Lestrade?" Sherlock demanded, and all of a sudden he had the upper hand, despite the erection and the flushed face.

"Drugs bust."

Of course, the rest of that night is history and things are a little awkward after John shoots the cabbie, but Chinese fixes that fine.

**A/N (again): I'm considering doing a second part involving actual orgasms after Chinese (try it, it's great) and I'm going to start posting these on LiveJournal to, so - lj slash novadiab1o**


	4. The Film

**A/N: Can live off comments and water for days on end. /hint /hint**

John was going through Sherlock's phone when he first saw the folder in his videos. Now John, he's not an invasive man, but when he sees something with his name on it in a phone his friend flatmate colleague gives him all the time to text and call and look through files in it, well, privacy sort of goes out the window.

Just because he happened to be in bed at the time of the discovery, and just because Sherlock wasn't at 221B didn't make it unusual. John could remember the exact text message he had sent for Sherlock, the exact time he had put it in his pocket, only to be found again three minutes ago.

John tapped open the folder and was attacked by an onslaught of caps of himself. He watched each one in order (because he had nothing better to do). 'John eating toast' was John eating toast (strawberry jam, sweet tea, looked to be filmed from the desk from the unusual angle), 'John shaving' was John shaving (however it was interrupted by very heavy breathing halfway through and cut short), 'John watching tele' was, shockingly, John watching the news. Slightly creepy was the three 'John sleeping' ones, one on the couch, the second in his bed and the third in a cab on the way home from God knows where.

Generally, John thought this was completely normal – for Sherlock. He was probably Sherlock's newest research topic.

Well, until he found the last one.

When he opened it, he recognised the interior of Sherlock's room immediately. Then Sherlock came into the screen, looking just a little flushed, and began to speak directly to the camera.

"John, one day I will show this to you."  
>John's eyebrows rose.<p>

"Right now you are in the shower. I was walking past and I heard you moan -."

John felt a flush creep up his neck.

Sherlock stopped for a moment as though collecting himself. He tried to start talking again, but his voice broke first go.

"Oh God, John, you really have no idea what you do to me. You…" Sherlock took a deep breath.

"I need to make this video to know that some day you might watch it, even though I'll probably delete it before you use my phone again."

Then Sherlock set the phone against the dresser.

All John could see was Sherlock's bed, and Sherlock, who was lying back onto it. But John couldn't bring himself to turn off the video, or do anything more than swallow loudly as he watched Sherlock unbuttoning his shirt, eyes closed and hands roaming over himself. The quality wasn't quite as rubbish as people made out, and John could clearly see Sherlock's defined stomach, and the stark whiteness against the black silk shirt.

Sherlock's room was small. John could hear clearly the increased breathing, the almost-moans, the tiny whimpers, and Christ, Sherlock hadn't even gotten his pants off yet.

_Yet._

John jumped though, when Sherlock moaned a quite 'Oh, John!' while _grinding_ against his own hand. In an undignified flurry, Sherlock no longer had any clothes on and he lay back, obviously trying to control himself.

His cock, not quite hard yet, was resting against his left hip, and his hands were on the side of his head and he was breathing in and out very deliberately.

Then he laughed, breathlessly. "As if I'll ever show this to you." He said bemusedly. "But oh God, what would you do I you did."

Obviously Sherlock thought he would do something very good, because he groaned and his cock twitched – actually, physically _twitched_.

Something in Sherlock broke after that, and suddenly his hand was around his length and his other hand was between his legs and he only stopped to lubricate with spit, before stroking again and fondling his sac with the other hand.

But John only noticed Sherlock was talking after a few moments. He wasn't loud or particularly coherent, it was just a long string of words that went a little like: "Oh God John, imagine you here, imagine you laying above me, just watching me as I bring myself of to the thought of you, God imagine your body above mine, imagine your arms next to my head - oh God holding my hands above my head – hnnng and your stomach, toned like it is and the your scar – "

At this point Sherlock's hand seemed to tighten at the base of his cock, a move John knew was used to stave off orgasm, when nothing else will work.

Sherlock's voice dropped lower: "That scar, the scar that has evaded me ever since I met you, I've never had a reason to even look at it, other than the fact that I just want to so much, oh I have dreams of glimpsing it, oh John, if you ever watched this, I can just imagine you lying in your bed watching me pulling on myself, I only ever think about you John, oh yes, only you, and the way you would feel inside me, your open lips against my neck as you came and unnnnnng."

Sherlock's tirade stopped then, and all John heard for the next few minutes was the slick noises of hand around appendage and Sherlock's breathy moans and eventually, semi-hysterical whimpers.

It was only a little after that when Sherlock sat bolt upright. He turned and looked straight at the camera, picking it up from the dresser and holding it close to his face.

"Now John," Sherlock huffed, his voice about three octaves too low, "watch carefully, because I might delete this before you see it."

John didn't care that the statement didn't make any sense because Sherlock was on his knees now, having replaced the phone, and stroking himself, closer to the camera than he was before.

And really ten strokes was all he had left in him. Because after that, the grunty-groany drawn out 'John', the white ribbons and the beautiful, perfect, wonderful expression all appeared simulataneously.

There wasn't much more of the video after that. A shot of Sherlock looked sheepish in his own semen reaching out for the phone, with a whispered "you'll never see this," and then black.


	5. The Film Part 2

John blinked a lot in the following three minutes.

At first he convinced himself it was to adjust to the changing light, but after a while he had to admit it was simply because he had no idea what to do next.

And of course, when John finally noticed the almost painful erection in his dirty, messy, just-chased-a-criminal-through-back-alleys pants and was about to do something about it was when Sherlock decided to burst in to the room.

So here John was, with Sherlock's phone in one hand, half of his cock in the other through the zip and his shirt half rucked up, and busted. Big time.

Sherlock, obviously, had been planning on making an announcement about the degradation of toenails in whale sperm or something like that, but he instantly froze, his eyes focussed on the pink device in John's hand.

Then he did something John had never seen him do before.

He swore.

A lot.

"Fuck. FUCK. Fuck shitting fuck tits cock wanker fuck crap ass dick shit shit shit fuck shit fucking SHIT."

And then he did a little tantrum dance and thumped down the stairs. With John at his heels.

Sherlock may be light on his feet but John is an army man. Army men don't just run down stairs, army men tear shit up.

So when John collided with Sherlock at the bottom of the stairs and they went flying into the wall hard enough to crack a few ribs, Sherlock was more surprised at the fact that John had an erection than the fact that he may actually have fractures.

"Now Sherlock," John said almost sweetly and Sherlock moaned angrily and tried to buck him off, "you can't just show me something like that and then not wait to see what I'd do." He sounded like Mrs Hudson, but he didn't care.

John pushed him harder against the wall. "Do you want to know what I'd do Sherlock?" he breathed into Sherlock's ear. Nothing except harsh breathing and panic. "Do you!" Almost yelled this time, another hard push.

"Yes!" Sherlock's voice broke and he closed his eyes, because he really couldn't take this much longer.

Then the pressure was gone, but Sherlock didn't open his eyes. Rustling, the return of warmth.

"Sherlock, open your eyes." John said, his voice very even.

And he did. And there it was. In all it's silvery, uneven glory. It wasn't ugly; in fact, as far as bullet wounds go it was quite attractive. It was just interesting. So, so interesting. And beautiful.

And when Sherlock put his mouth on it and John shivered, that was beautiful too. John yanked his face up into a crushing kiss and the spell was broken, but that was okay because his tongue was in John's mouth and everything that was happening was the best thing ever really.

Sherlock wrapped his arm around John's chest and they were flush together and so, so perfect, and there wasn't even tongue anymore, just eye contact and lips, and breath, little carbon dioxide molecules that had been through John where now in him and wasn't was quite wonderful?

And now John was just pecking at his lips. Just enough to make Sherlock follow him back.

"How do you even exist?" John mumbled against his lips. And Sherlock shrugged because he didn't know.

What he did know is that they both had erections and that it was scientifically proven that it felt nice to rub such appendages together. And of course Sherlock doesn't do things in halves, or slowly, so soon they were both out and sliding deliciously. And John's hands brushed his and suddenly, without even realising, he was on his knees and John's hands were now in his hair and he moaned so loud Mrs Hudson would have a smug smile for days.

Sherlock could feel the saliva dribbling down his chin and John's eyes watching him, and that was also the best thing ever. Even when Sherlock choked and had to pull away, it felt amazing, having John in his mouth and causing his hands to scrabble against the wall for a hold before he slumped on the ground in front of Sherlock, suitably incoherent. His coherency didn't improve when Sherlock leaned over him on all fours. Sherlock, flushed red and shaking with anticipation and arousal, sweating and sucking the pre-come off his bottom lip, with his hands either side of hips. But its Sherlock's eyes that do him in. The irises are almost black, the pupils blown with only a ring of grey-blue-green around them. The lids were half closed, with red rims, yet they still had that Sherlockian spark of intelligence, something John could never fuck out, but damn him if he wasn't going to try. Sherlock looked like fornication personified and that was why, without any stimulation other than Sherlock's (garlicky, not that John noticed) breath on his face, John came with a groan.

When John came to, Sherlock was nuzzling behind his ear and thrusting steadily against his thigh.

"You've ruined my plans for this evening," Sherlock comments deviously. John tried to catch his breath in reply. "Although I could just fuck you, instead."

For a man who not long ago was having a meltdown because his flatmate saw him wanking, he seemed far too sure of himself. John, with a muttered 'got your breath back?', hauled Sherlock up and half-dragged him up the stairs.


End file.
